Novel process for the preparation of 1,5-bis-dehydro steroids



United States Patent C) Jersey No Drawing. Filed July 7, 1964, Ser. No. 380,907 4 Claims. (Cl. 260-3914) This application is a continuation-in-part of applicants copending application Serial No. 312,273, filed September 30, 1963, now abandoned.

This application relates to a novel process for effecting a partial deconjugation of a cross-conjugated system in steroids. More particularly, this application relates to a process for converting a 3-keto-A steroid to a 3-keto- A steroid.

Specifically, by my process, a steroid having a 3-ket0- A -cross-conjugated system is subjected to the action of an alkali metal alkoxide, such as potassium tertiarybutoxide and sodium ethoxide in a solvent selected from the group consisting of a lower dialkyl sulfoxide, e.g., dimethylsulfoxide and diethylsulfoxide, and a lower dialkyl alkanoic acid amide, e.g., dimethylformamide, diethylformamide, and dimethylacetarnide.

My process is most advantageously carried out utilizing potassium tertiary-butoxide as the deconjugation agent and dimethylsulfoxide as solvent.

In a preferred mode of my invention, a 3-keto-1,4- androstadiene, e.g., 17a-methyl-1,4-androstadiene-l7fl-ol- 3-one, is allowed to react with potassium tertiary-butoxide in dimethylsulfoxide at room temperature for a short period of time, i.e., from about 15 to 30 minutes. Isolation of the resulting S-keto-1,5-dehydro-steroid, e.g., 17u-methyl-1,5-androstadiene-l7B-ol-3-one may be effected by diluting the reaction mixture with ice Water, for example, and either filtering the resultant precipitate or, preferentially, by extracting the diluted aqueous reaction mixture with an inert organic solvent such as methylene chloride, chloroform, or ethyl acetate. Purification of the isolated 3-keto-A steroid is effected by crystallization or by chromatographic techniques well known in the art.

In my process, the choice of solvent is critical, it being necessary to use either a di-alkylsulfoxide or a di-lower alkyl alkanoic acid amide as solvent in order to effect deconjugation of a 3-keto-A system by mean of an alkali metal alkoxicle. For example, when l7a-methyl1,4- androstadiene-l7fi-ol-3-0ne is reacted with potassium tertiary-butoxide in dimethylsulfoxide according to my process, the corresponding A steroid, i.e., 17a-methyll,S-androstadiene-l7fl-ol-3-one is isolated in good yield, i.e., from about 40-70% the theoretical yield; whereas, when solvent such as tertiary-butanol, benzene, and diglyme (diethylene glycol dimethyl ether) are used, deconjugation does not occur.

In my process, when the starting steroid has a cortical side chain such as in prednisone, it is preferable to protect the side chain at C-17 prior to reaction with the alkali metal alkoxide in order to minimize possible competing reactions, such as the rearrangement of the side chain to form a D-homo steroid, or reaction of the free hydroxy functions with the alkali metal alkoxide to form the corresponding alkali metal salt. Typical derivatives suitable for protecting the cortical side chain are the l7,20;20,2l-bis-methylenedioxy function and the 17,21 acetonide derivative, which are prepared by procedures well known in the art. Thus, prednisone may be converted to either the corresponding 17,20;20,21-bis-methyl enedioxyor 17,2l-acetonide-derivatixe, and when each are reacted with potassium tertiary-butoxide, for example, there is obtained the corresponding 3-keto-A derivative, namely, 17,20;20,2l-bis-methylenedioxy-Li pregnadiene-3,1l-dione or 1,5-pregnadiene-17u,21-dio1-3, 11,20-trione 17,2l-acetonide, respectively. Mild acid hydrolysis of each of the foregoing derivatives yields 1,5- pregnadiene- :,2 1-diol-3 ,1 1,20-trione.

In 1,4-pregnadienes not having a cortical side chain but having a l7a-hydroxy function, such as l7a-hydroxyl-dehydroprogesterone, preparation of a 20-ketal derivative, e.g., the 20-ethylene ketal, according to known procedures is desirable prior to reaction with the alkali metal alkoxide in dialkylsulfoxide or a dialkyl alkanoic acid amide, e.g., potassium tertiary-butoxide in dimethylsulfoxide. Thus, 17a-hydroxy-l-dehydroprogesterone is reacted with ethylene glycol and the resulting l7a-hydroxy-ZO-ethylenedioxy-l-dehydroprogesterone subjected to the action of potassium tertiary-butoxide in dimethylsulfoxide according to my process whereby one obtains 17a 'hydroxy 20 ethylenedioxy 1,5 pregnadiene 3- one. Cleavage of the 20-ketal is effected in a weak acid medium according to known techniques to obtain the free 20-keto compound, 17a-hydroxy-l,5-pregnadiene-3,20- dione.

In those 1,5-pregnadienes devoid of a l7a-hydroxy function, e.g., l-dehydroprogesterone, protection of the 20-ketone prior to reaction with potassium tertiarybutoxide, for example, is not necessary.

The starting compounds for my process may be any steroid having a 3-keto-A system in the A ring, with those having either a 17a-hydroxy-17B-acetyl or a cortical side chain at C-17 being preferably protected as described hereinabove. Thus, suitable starting steroids include 3-keto-l,4-pregnadienes, such as prednisone (1,4- pregnadiene 17rx,21 diol 3,11,20 trione), prednisolone (1,4 pregnadiene 11B,l7u,21 triol 3,20- dione), dexamethasone (9u-fluoro-l6a-methyl-l,4-pregnadiene 11B,17a,21 triol 3,20 dione), oat-methyl 1,4- pregnadiene l1fl,17cz,2l triol 3,20 dione, 60c fluoro- 1,4 pregnadiene 1l[5,17a,21 triol 3,20 dione, 1 dehydroprogesterone (l,4-pregnadiene-3,20-dione), 17a-hydroxy l dehydroprogesterone (1,4 pregnadiene- 17a-ol-3,20-dione), and 3-keto-1,4-androstadienes, such as, l-dehydro-testosterone (1,4-androstadiene--01-3- one) and 17ot-methyl-1,4-androstadiene-l7 8-ol-3-one. The 3-keto-A steroidal starting compounds of my process need not necessarily be a member of the pregnane or androstane series, it being only necessary that the starting compounds possess a 3-keto-A steroid and that any reactive groups be preferentially protected as described hereinabove.

It is thus apparent from the foregoing, that the 3-keto- A starting compounds of my novel proces may be substituted at one or more carbons on the steroid nucleus, particularly at positions 2, 4, 6, 9, l1, and 16, which substituents are introduced by methods well known in the art.

In my process we usually use an excess of alkali metal alkoxide, e.g., potassium t'ertiary-butoxide, sodium ethoxide, sodium methoxide, with respect to the molar quantity of the 3-keto-A -starting steroid. In general, there should be present for each mole of starting 3-keto-A -steroid at least an equimolar quantity of alkali metal alkoxide plus an added molar quantity for each hydroxyl group or ester thereof that may be present; although even larger molar excesses of basic agent may be used. Thus, when converting 17a-methyl-l,4-androstadiene-17B-ol-3-one to the corresponding 1,5-diene by my process there should be present at least two moles of the alkali metal alkoxide, e.g., potassium tertiary-butoxide for each mole of steroid.

My process may be eifected from temperatures ranging from about C. to about 40 C. and preferably in the range of about C. to 35 C. and usually at about room temperature. In general, the solvent used in my process should, therefore, have a melting point lower than about 40 C.

In my novel process the conversion of a 3-keto-A steroid to a 3-keto-A -steroid takes place within a relatively short time and, in general, within a half hour.

Under the conditions of my process, an ester group present in the starting steroid may remain unchanged depending upon the reaction time employed, the less hindered becoming hydrolyzed sooner than the more hindered esters. By regulating the reaction time in our process, one can regulate the degree of saponification and thereby the amount of ester remaining in the product. For example, 17x-methyl-1,4-androstadiene-175-01-3-one l7-acetate may be subjected to potassium tertiary-butoxide in dimethylsulf'oxide at room temperature for three hours and be transformed principally to l7a-methyl-l,5-androstadiene-17fl-ol-one. If the reaction is terminated in '15 minutes, a substantial amount of the 3-keto-l,S-diene 17- acetate may be obtained.

My process whereby a 3-keto-A -steroid is converted to a 3-keto-A -steroid is preferentially, although not necessarily, carried out under an inert atmosphere, such as, argon or nitrogen. For example, when the starting steroid contains a halogen substituent, e.g., 6ot-fiuoroprednisolone, optimum yields of the corresponding 1,5- dieneone, 6 fluoro-LS-pregna-diene-l1,6,l7u,21-triol-3,20- dione are obtained when my process is carried out under an inert atmosphere.

In my process, after reaction of a 3-keto-A -steroid with potassium tertiary-but-oxide in dimethylsulfoxide, for example, the desired 3-keto-A -steroid is isolated by first adding the reaction mixture to a protic reagent, i.e., a proton donor medium such as water, an alcohol, or an acid, followed by extraction of the 3-keto-A -steroid with a suitable organic solvent. Water is most generally used as the protic agent, either alone or together with an alcohol such as methanol or ethanol, or together with a suitable acid, e.g., lower alkyl fatty acid, such as acetic acid, or with other weak acids such as boric acid and phenol. For optimum yields, it is important that after addition of the reaction mixture to the protic reagent, the resultant protic medium be suitably buffered to a pH near neutrality, and/ or the 3-keto-1,5-bis-dehydro product be immediately extracted from the protic medium. Thus, for example, after reacting l7a-methyl-1,4-androstadiene-17B- o1-3-one with potassium tertiary-butoxide in dimethylsulfoxide according to my process, and addition of the reaction mixtur'e to ice water (as the protic reagent), best results are obtained when the 1,5-bis-dehydro steroid, 17amethyl-1,5-androstadiene-l7 3-ol-3-one is immediately extracted with an organic solvent and the extracts washed to neutrality.

By my process there may be prepared therapeutically valuable 3-keto-1,5-pregnadienes such as the following described in US. Patent No. 2,908,696.

CHzOR Y ---orr 1,5-pregnadienes may now be prepared by my process which eliminates the necessity of preparing an intermediary 6-substituted steroid, many of which are difiicult to prepare.

My process is of particular value in preparing 3-keto- 1,5-androstadienes, such as the orally effective anabolic agents, l7a-methyl-1,5-androstadiene-17fi-o1-3-one and esters thereof described in the co-pending application of Shapiro and Oliveto, Serial No. 251;,747, filed I anuary 16, 1963, now US. Patent No. 3,127,430.

The 3-keto-1,S-androstadienes and 3keto-1,5-pregnadienes prepared from the corresponding A -steroids by my process are also valuable as intermediates in preparing the corresponding 3 (u and B)-hydroxy-A -steroids, a new class of compounds described in the application of Tanabe and Oliveto, Serial No. 263,441, filed March 7, 1963. These '3-hydroxy-L5-dienes, in general, exhibit enhanced activity over their respective 3-keto precursor. Many of the 3-hydroxy-1,5-diene transformation products are themselves useful intermediates, such as in the preparation of 6-substituted analogs, e.g., 6-fiuoro, methyl, and the like.

Thus, a 3-keto-l,5-diene, e.g., 17a-methyl-l,5-androstadiene-l7/3-ol-3-one, upon reduction by means of an alkali metal aluminum or borohydride (lithium aluminum hydride, sodium borohydride, etc.), or a metal alkoxide (e.g., aluminum isopropoxide) or aluminum tertiarybutylate is converted to the corresponding 3-hydroxy-l,5- diene, e.g., l7u-methyl-1,5-androstadiene-3 (or. and ,8),17}8- diol, separable via fractional crystallization and chromatographic techniques into the 3ocand 3fi-hydroxy isomers, 17ot-methyl-1,5-androstadiene-3u,l{7}8-diol and 17amethyl 1,5-androstadiene-3/3,17fl-diol, respectively, both of which are valuable as anabolic agents.

Prior to reduction of a 3-keto-1,5-diene to a 3-hydroxy-1,5-diene by the above-described process, any ketones present at 0-17 or 0-20, in the case of pregnadienes, should preferably be protected by a group such as an ethylene ketal or bis-methylenedioxy derivative. Thus, for example, the 17,20;20,2l-bis-methylenedioxy derivative of 1,5-pregnadiened113,170:,2ltriol-3;20-dione is reduced with sodium borohydride in water to the 17, 20;20,2l-bis-methylenedioxy derivative of 1.5-pregnadi- 6I16-3(oz and fi),11/8,l7oa,2l-tetrol-20-'one, which upon mild acid hydrolysis will yield 1,5-pregnadiene-3(a and [8),11fl,17a,2l-tetrol-20-0ne, separable to the 30cand 3;?- hydroxy isomers via chromatographic techniques, both of which are valuable as anti-inflammatory agents.

In the conversion of a 3-hydroxyl-1,5-diene to a 3- ket'o-6-substituted-1,4-diene, the transformation is effected utilizing known techniques. After protection of any ketone present at 0-17 or C-20, epoxidation of the -A bond by means of a per-acid followed by treatment of the resulting 50,6a-6POXY with hydrofluoric acid or a Grignard reagent such as methyl magnesium iodide yields the corresponding 5a-hydroxy-6fl-fluoroor Sa-hydroxy- 6fiI-methyl-A -35-ol intermediate, respectively. Chromic acid oxidation of the 3fi-hydroxy to a 3-keto group followed by dehydration of the 5a-hydroxy function with a reagent such as thionyl chloride in pyridine will yield the corresponding 3-keto-6fi-fluoroand 3-keto-6B-methyl-1,4-dienes, respectively. Epimerization to the 6aisomers may be effected with a base such as potassium tertiary-butoxide in tertiary-butanol to obtain the 3-keto- 6a-flUOIO- and 3-keto-6a-methyl-1,4-dienes, respectively.

Compounds of the following general formula which may be prepared from the corresponding 3-keto-1,4-dienes by my novel process are illustrative of the 3-keto- 1,5-diencs useful as intermediates in the production of the corresponding 3-hydroxy-1,5-dienes:

wherein A represents hydrogen, lower alkyl, a-hydroxy, and u-lower alkanoyloxy; B represents hydrogen, methyl, and fluoro; Y represents keto, (H,5OH), (H,aOH), and (fie-halogen); X represents hydrogen and halogen, and when Y is (H,aOH), X is hydrogen, and when Y is (H,fl-halogen) X is halogen; and X and Y together represent an epoxy or a 9(11)-bond; and Z is a member of the group consisting of ii, J3...D,and c=0 R being a member of the group consisting of hydrogen or lower alkanoyl; D being a member of the group consisting of hydrogen, lower alkyl, ethinyl, halogenoethlnyl, or alkyl ethinyl; V being a member of the group consisting of hydrogen, hydroxy, and lower alkanoyloxy; and Q is a member of the group consisting of hydrogen, hydroxy, acyloxy, halogen, or lower alkyl.

The following are examples to illustrate the novel process of this invention, but are not to be construed as limiting, the scope of my invention being limited only by the appended claims.

Example l .-1 7a-methyl-1,S-androstadiene- 1 7B-0l-3-0ne Example 2.] 7u-methyl-1,S-androstadiene- 17fi-0l-3-0ne 17-acetate A. J7a-methyl-1,4-andr0stadiene-17fl-0l-3-0ne 17-acetate.Dissolve 17oz methyl-1,4-androstadiene-175-01-3- one (0.1 g.) in 1 m1. of pyridine and 0.5 ml. of acetic anhydride. Heat the reaction mixture on the steam bath for 6 10-20 hours. Dilute with water followed by additional dilution with aqueous hydrochloric acid. Filter the resultant precipitate of substantially 17a-methyl-1,4-androstadiene-l7B-ol-3-one 17-acetate. Purify by crystallization from aqueous methanol.

B. 17a-methyl-1,5-andr0stadiene-17/3-0l-3-0ne 17-acetate.-To a solution of 1 g. of 17u-methyl-1,4-androstadiene-17B-ol-3-one 17-acetate in 15 ml. of dimethylsulfox ide cooled, add 0.5 g. of potassium tertiary-butoxide. Stir for approximately 15 minutes allowing the temperature of the reaction mixture to slowly rise to room temperature. Pour into ice water; extract with methylene chloride; then wash the combined methylene chloride extracts with water. Evaporate the methylene chloride extracts to a residue. Chromatograph the residue over silica gel eluting with hexane containing increasing percentages of ether. Combine the like eluates as determined by ultraviolet evaluation and thin layer chromatography and evaporate to a residue comprising l7a-methyl-1,S-androstadiene-l7fi-ol-3-one 17 acetate. Purify by crystallization from acetone-hexane. M.P. 163-166 C.

In the above-described procedure, by changing the reaction time from 15 minutes to 5 hours, there is obtained the 17-alcohol, e.g., l7u-methyl-1,5-androstadiene-17/3- ol-3-one.

Treat 1,4-androstadiene-l7,8-ol-3-one with potassium tertiary-butoxide in dimethylsulfoxide in the manner described in Example 1. Isolate the resultant product in the manner described to obtain 1,5-androstadiene-17fl-ol- 3-one.

Example 4.1,5-pregnadiene-11fi,1 7a,21 trial-3,20-dione A. 17,20;20,21 bis methylenedioxy 1,5 pregnadiene-I1fl-0l-3-one.ln a manner similar to that described in Example 1, except that the reaction is con-' ducted under an atmosphere of nitrogen, treat l7,20;20, 2l-bis-methylenedioxy-1,4-pregnadiene-l1;8-ol-3-one with potassium tertiary-butoxide in dimethylsulfoxide. Isolate the resultant product in the described manner to obtain 17,20;20,21 bis methylenedioxy 1,5 pregn'adienel1/8-ol-3-one. Purify by crystallization from acetone followed by chromatography on silica gel eluting with etherhexane. Combine like fractions based on ultraviolet evaluation followed by crystallization from acetone. M.P. 244-246 C.

In a similar manner, 6u-methyl-17,20;20,21-bis-methy1- enedioxy-1,4-pregnadiene-llB-ol-3-one, 6oc-flllOI'O-l7,20; 20,21 bis methylenedioxy 1,4 pregnadiene 11 3 ol- 3-one, and a fluoro 16oz methyl 17,20;20,21 bismethylenedioxy-1,4-pregnadiene-l lfi-ol-3-One are each reacted with potassium tertiary-butoxide in dimethylsulfoxide and their respective resultant products isolated in the above-described manner to yield, respectively, 6-methyl- 17,20;20,21 bis methylenedioxy 1,5 pregnadiene- 11/3 ol 3 one, 6 fluoro 17,20;20,21 bis methylenedioxy 1,5 pregnadiene 11B ol 3 one, and 90afluoro 16a methyl 17,20;20,21 bis methylenedioxy- 1,5-pregnadiene-11,8-01-3-one.

B. 1,5 pregnadiene-J1B,]70:,21-tri0l-3,20-di0ne.Dissolve 0.1 g. of 17,20;20,2l-bis-methylenedioxy-1,5-pregnadiene--ol-3-one in 12 ml. of 70% aqueous acetic acid. Allow the solution to remain at room temperature for 48 hours; then dilute with water and extract with chloroform. Combine the chloroform extracts and evaporate to a residue comprising 1,5-pregnadiene-l1,8,17a,21-tri'ol- 3,20-dione.

In a similar manner, treat each of the bis-methylenedioxy-1,5-dienes prepared in the second paragraph of Example 4A with 70% aqueous acetic acid to obtain, respectively, 6 methyl 1,5 pregnadiene llfl,l7oc,21-

7 triol 3,20 dione, 6 fluoro 1,5 pregnadiene l1fi,17oz, 21 triol 3,20 dione, and 90a fluoro 16a methyl- 1,5-pregnadiene-11/3, 17a,21-triol-3,20-dione.

Example 5 .-1 ,5 -pregnadiene-1 7 :,21 -diol- 3,11,20-tri0ne A. 1,5 pregnadiene 17oc,21 dial 3,11,20 trion e 17,21-acetonide.-In a manner similar to that described in Example 1, allow 1,4-pregnadiene-17a,21-diol-3,11,20- trione 17,2l-acetonide to react with solid potassium tertiary-butoxide in dimethylsulfoxide for 30 minutes. Isolate the resultant product in the described manner and purify from acetone-hexane to give 1,5-pregnadiene- 17oz,21-dl0l-3,11,20-1110116 17,21-acetonide.

B. 1,5 pregnadiene 170;,21 diol 3,11,20 trione.Dissolve the 1,5-pregnadiene-l7a,2l-diol-3,11,20- trione 17,21-acetonide prepared in Example A in 3 ml. of 90% aqueous acetic acid. Allow the resulting solution to remain at room temperature for approximately 17 hours, then dilute with Water. Collect the resulting precipitate of 1,5-pregnadiene17u,21-diol-3,11,20-trione by filtration. Purify by pouring a methylene chloride solution of the 1,-5-p-regnadiene-l7a,2l-diol-3,11,20-trione onto a Florisil column dampened with methylene chloride. Elute first with methylene chloride; then with methylene chloride/ acetone mixtures; combine the fractions of methylene chloride together with those methylene chloride/acetone mixtures which by spectroscopic (U.V.) evaluation contain substantially the 3-keto-1,5- diene product. Concentrate the combined fractions in vacuo to a residue comprising 1,5-pregnadiene-17a,2ldiol-3,1 1,20-trione.

Example 6 .l 7 a-hydro-xy-I ,5 -pregnadiene-3,20-di one A. 20 ethylenedioxy 1,,4 pregnaa'iene 17a ol 3- one.Reflux a solution of 1 g. of 17oc-hYdlOXY-1-d6hYdlO- progesterone in 50 ml. of anhydrous benzene and 0.23 ml. of ethylene glycol under a Dean-Stark separator for 4 hours in the presence of 10 mg. of p-toluenesulfonic acid. Cool the mixture, then make slightly basic by the addition of 10% sodium hydroxide. Separate the organic layer; wash to neutrality with water; and concentrate in vacuo to a residue comprising 20-ethylenedioxy-1,4-pregnadiene-17a-ol-3-one.

B. 20 ethylenedioxy 1,5 pregnadiene 17a o'l 3- 0ne.Allow 20 ethylenedioxy 1,4-pregnadiene 17w ol-3-one to react with potassium tertiary-butoxide in dimethylsulfoxide in the manner described in Example 2; isolate the resultant product in the described manner to 8 give 20 ethylenedioxy 1,5 pregnadiene 17a ol 3- one.

C. 1,5-pregnaa iene-17a-0l-3,20-di0ne.Dissolve 0.1 g. of 20ethylenedioxy-1,5-pregnadiene-17a-ol-3-one in 12 ml. of aqueous acetic acid. Allow the solution to remain at room temperature for 17 hours; then dilute with water and extract with chloroform. Combine the chloroform extracts and evaporate to a residue comprising 1,5- pregnadiene-l7a-ol-3,20-di'one.

Example 7.],5-pregnadiene-3,20-di0ne In a manner similar to that described in Example 1, allow 1,4-pregnadiene-3,20-dione to react with potassium tertiary-butoxide in dimethylsulfoxide for 30 minutes. Isolate the resultant product in the described manner and purify by crystallization from acetone-hexane to give 1,5-pregnadiene-3,20-dione.

I claim:

1. The process for preparing a 3-keto-l,5-bis-dehydrosteroid of the androstane and pregnane series which comprises reacting a steroid selected from the group consisting of a 3 keto 1,4 bis dehydro androstane and a 3 keto 1,4 bis dehydro pregnane with an alkali metal alkoxide in a solvent selected from the group consisting of a di-lower alkylsulfoxide and an N,N-di-lower alkyl alkanoic acid amide.

2. The process for preparing a 3-keto-1,5-bis-dehydrosteroid of the androstane and pregnane series which comprises reacting a steroid selected from the group consisting of a 3 keto 1,4 bis dehydro androstane and a 3 keto 1,4 bis dehydro pregnane with an alkali metal alkoxide in a solvent selected from the group consisting of a di-lower alkylsulfoxide and an N,N-di-lower alkyl alkanoic acid amide; and isolating the 3-kcto-l,5- bis-dehydro-steroid thereby produced.

3. The process for preparing a 3-keto-1,5bis-dehydrosteroid of the androstane and pregnane series which comprises reacting a steroid selected fromthe group consisting of a 3-keto-1,4-bis-dehydro-androstane and a 3-keto-1,4- bis-dehydro-prcgnane with potassium tertiary-butoxide in dimethylsulfoxide.

4. The process for preparing 17a-methyl-1,5-androstadiene l7fi-ol-3-one which comprises reacting 17a-methyl- 1,4-androstadiene-17,8-01-3-one with potassium tertiarybutoxide in dimethylsulfoxide.

No references cited.

LEWIS GOTTS, Primary Examiner. 

1. THE PROCESS FOR PREPARING A 3-KETO 1,5-BIS-DEHYDROSTEROID OF THE ANDROSTANE AND PREGNANE SERIES WHICH COMPRISES REACTING A STERIOD SELECTED FROM THE GROUP CONSISTING OF A 3-KETO-1,4-BIS-DEHYDRO-ANDROSTANE AND A 3-KETO-1,4-BIS-DEHYDRO-PREGNANE WITH AN ALKALI METAL ALKOXIDE IN A SOLVENT SELECTED FROM THE GROUP CONSISTING OF A DI-LOWER ALKYLSUFOXIDE AND AN N,N-DI-LOWER ALKYL ALKANOIC ACID AMIDE. 